package itheima_02;

public class IntegerDemo2 {
    public static void main(String[] args) {
        Integer i1 = new Integer(100);
        System.out.println(i1);
        Integer i2 = new Integer("100");
        System.out.println(i2);
//        Integer i3 = new Integer("abc");
//        System.out.println(i3); NumberFormatException,不能是字母,只可以是数字！
        Integer i4 = Integer.valueOf(100);//int ---- Integer
        System.out.println(i4);
        Integer i5 = Integer.valueOf("100");//也不可以是字母!
        System.out.println(i5);//string ---- Integer
    }
}
